对呼吸中枢产生麻醉和抑制效应（）

A.PaO降至60mmHg时
B.PaO迅速降40～50mmHg时
C.PaO低于30mmHg时
D.PaO低于20mmHg时
E.PaCO高于80mmHg

A.PaO为50mmHg，PaCO为40mmHg
B.PaO为55mmHg，PaCO为50mmHg
C.PaO为65mmHg，PaCO为40mmHg
D.PaO为70mmHg，PaCO为40mmHg
E.PaO为70mmHg，PaCO为45mmHg

A.PaO为50mmHg，PaCO为40mmHg
B.PaO为55mmHg，PaCO为50mmHg
C.PaO为65mmHg，PaCO为40mmHg
D.PaO为70mmHg，PaCO为40mmHg
E.PaO为70mmHg，PaCO为45mmHg